This invention relates to post-mix drink dispensing systems, and in particular to a new and improved system for simultaneous dispensing of soda and syrup in separate flow paths for subsequent mixing.
A wide variety of drinks are dispensed in post-mix dispensers with a syrup or other concentrate and a carbonated water or other diluent provided from separate sources and controlled by valve arrangements for mixing in the outlet nozzle of the dispensing apparatus. Some of the dispensers are electrical, with the valves being operated by electrical switches and solenoids, and some are mechanical, being operated by manually pushing a botton or a lever. The present invention is directed to a mechanical type dispenser.
In one type of mechanical dispenser, the valving is controlled by push buttons adjacent the outlet nozzle. In another mechanical type of system, usually known as a touch faucet, the valving in controlled by a lever positioned adjacent the outlet nozzle and the lever is actuated by the operator pushing the drink cup against the lever. This type of device is widely used in refreshment stands, fast food restaurants and self-service establishments.
Often the drink cup used with a touch faucet dispenser is a non-reusable item and hence it is desirable to have the cup made of a minimum amount of material. These types of cups are relatively flexible and easily distorted or collapsed, particularly when being forced against the lever of a touch faucet dispenser. Therefore it is desirable that the dispenser be operable with a minimum of force. However at the same time, the valving arrangement needs to have positive seating in order to avoid leakage which is both messy and costly in lost materials.
All valve mechanisms use some sort of moving component or poppet which rests against another component or seat to provide a sealing arrangement. Opening of the valve for fluid flow between the poppet and the seat requires force sufficient to break the hydrostatic seal between the poppet and seat as well as sufficient to move the poppet. Prior art post-mix dispensing systems have been of two types. In one arrangement, separate valves have been used for the syrup and for the soda, with the valve chambers usually arranged in parallel, with a separate poppet sliding in each chamber. The actuating mechanism engages both poppets at the same time and moves both from the closed or sealing position to the open or flow position. In the other arrangement, a single valve poppet is positioned in a single valve chamber having two valve seats. Two separate seat engaging lands are provided on the valve poppet spaced so as to simultaneously engage the two valve seats. In both of theses arrangements, actuation of the dispenser requires breaking of two hydrostatic seals at the same time as the poppet or poppets are moved.